Problem solving > Controller and I/O

Does the controller have an X indicator?

The indicator appears for nodes that are not communicating. Typically, this indicator occurs when there is a bad connection or the controller is not powered up. To clear this indicator, go to the node and make sure that it is connected, that the wiring is correct and sound, and that the node is powered up. This indicator also occurs for a few seconds after a controller is commissioned.

Possible Cause

Corrective action

Control network cable is not working correctly.

Test the cable between the controller and the hub. If the cable is not working correctly, repair or replace it.*

You are looking at the wrong controller.

Use the Identify Controller function in the DeltaV Explorer Node Properties dialog to flash the controller LEDs.

Primary and secondary control network connections are crossed.
  1. Use the Identify Controller function in the DeltaV Explorer Node Properties dialog to flash the controller LEDs.
  2. Verify that the primary control network cables are connected to the correct primary ports on the controller, workstation, and hub.
  3. Verify that the secondary control network cables are connected to the correct secondary ports on the controller, workstation, and hub.

Primary and secondary IP addresses are switched.

Check the IP addresses for the primary and secondary control networks (using Workstation Configuration). If switched, the DeltaV system does not communicate with the controller, but the controller appears to be commissioned (lights indicate this). The only evidence is that the controller is listed with the indicator in DeltaV Explorer.

*For more information about cable connections, refer to DeltaV S-series and CHARMs Hardware Installation.